This invention relates to an improved bus support for supporting an energized cylindrical tubular bus beyond an outer end of an insulator.
Many existing bus supporting structures are made from a single casting. The use of a single casting imposes serious limitations on the design of the structure. For example, the cores used during casting to define the openings in the hooks of the support occasionally shift during the casting operation causing the openings to be in misalignment and the dimensions of the bus support thus to be in error. When this occurs, the bus will not slidably fit within the openings in both hook portions. Also, the use of a single casting restricts the shape of the structure because of the procedure of molding that includes the removal of the cast from the mold. Hence, the most desirable design from a corona standpoint cannot be obtained. Furthermore, in the case of a single casting, recesses in the inner surface of the hook portions which receive static-eliminating leaf springs must be so oriented that the sides of the springs are perpendicular to the longitudinal axis of the bus permitting sharp edges to abrade the bus as it moves longitudinally within the bus support.
Another problem with existing bus supports is of breakage which occurs where the hooks intersect the base and between the perimeter of the base and one of the apertures for bolts which secure the support to the insulator. The breaks occur at these places because forces, such as can be caused by wind, applied along a longitudinal axis of the bus toward an inner side of a hook portion are exerted upon a lever arm defined by the distance between a point of contact of the force on the inner side of the hook portion and a point of rotation at a point along the connection of the hook portion and the base. Thus, the bus support is subjected to a moment which is the product of the force and a relatively short lever arm.
A need exists for an improved bus support design having improved corona and strength characteristics.